Coil suspension arrangement for a cathode ray tube

ABSTRACT

A gimbals whose axes initially are at right angles to the long axis of a cathode ray tube, supports a coil, such as the focusing coil, on the neck of the tube. Adjustment screws in arms extending from the outer and inner gimbals, respectively, permit movement about its axis of the outer gimbal relative to the gimbals supporting structure and movement about its axis of the inner gimbal relative to the outer gimbal. A single spring secured between the inner gimbal arm and the gimbals supporting structure maintains the gimbals and coil in the position to which they have been adjusted.

United States Patent Goldammer et al.

[15] 3,657,674 [451 Apr. 18, 1972 COIL SUSPENSION ARRANGEMENT FOR A CATHODE RAY TUBE Freeland Robert Goldammer, Princeton; Harold Denton Albrecht, Jr., Camden, both of NJ.

Assignee: RCA Corporation Filed: Aug. 28, 1970 Appl. No.: 67,755

lnventors:

References Cited UNITED STATES PATENTS Lanctot et al ..343/765 3,321,577 5/1967 Burke et a1 ..335/210 X 2,440,403 4/1948 Jackson ..335/212 3,330,979 7/1967 Constantine ..335/212 X Primary Examiner-George Harris Att0rneyl-l. Christoffersen [5 7] ABSTRACT A gimbals whose axes initially are at right angles to the long axis of a cathode ray tube, supports a coil, such as the focusing coil, on the neck of the tube. Adjustment screws in arms extending from the outer and inner gimbals, respectively, permit movement about its axis of the outer gimbal relative to the gimbals supporting structure and movement about its axis of the inner gimbal relative to the outer gimbal. A single spring secured between the inner gimbal arm and the gimbals supporting structure maintains the gimbals and coil in the position to which they have been adjusted.

12 Claims, 3 Drawing Figures Patented April 18, 1972 INVENTORS. Freeland R Goldammemm Harold D. Albrecht, Jr.

BY I.

A TTORNE Y COIL SUSPENSION ARRANGEMENT FOR A CATHODE RAY TUBE BACKGROUND OF THE INVENTION It is known in the prior artto support a coilsuch as the focussing coil of a cathode ray tube on the neck of the tube by means of a gimbals. An example of such a supporting structure may be found in U.S. Pat. No. 2,440,403 to D. Jackson issued Apr. 27, 1948. The gimbals is supported in a housing and each gimbal ring is adjusted in position about its axis by a separate adjustable bolt passing through the housing. The two gimbal rings are maintained in the positions to which they are moved by the bolts, by two springs, each secured between its gimbal ring and the housing.

While the above arrangement may be satisfactory for some applications, in one particular situation it was found that an excessive amount of space was required for the two springs and the gimbals were difficult to position. The object of this invention is to provide a new and improved gimbals suspension for a coil which is relatively simple,,which occupies a'relatively small amount of space and which can be maintained in the position to which it is adjusted by a single spring.

SUMMARY OF THE INVENTION A coil of a cathode ray tube is suspended about the neck of the tube and is tilted about two axis, perpendicular to one another and to the long axis of the tube. An inner gimbal supports the coil, and the inner gimbal is supported in an outer gimbal for permitting tilting of the inner gimbal about the inner gimbal axis. The outer gimbal is supported in agimbal supporting structure which is fixed to a chassis, for permitting tilting of the outer gimbal about the outer gimbal axis. Adjusting means are mounted between the inner and outer gimbal for tilting the inner gimbal about its axis, and adjusting means are mounted between the outer gimbal and the gimbal supporting structure for tilting the outer gimbal about its axis. Biasing means are coupled between the inner gimbal and the chassis for maintaining the inner and outer gimbals in the positions to which they have been adjusted.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front elevation of the device embodying the invention.

FIG. 2 is a side elevation view of the device shown in FIG. 1.

FIG. 3 is a top elevation view of the device shown in FIGS. 1 and 2.

DETAILED DESCRIPTION The suspension system of the embodiment of the invention shown in the figures includes an outer supporting ring 2 which is secured to the chassis (not shown but indicated schematically by the symbol 3) by the member 4. The outer gimbal 6 is secured by pins 14 and 16 to the supporting ring 2 and the inner gimbal 8 is secured to the outer gimbal by pins 32 and 34. The coil 10 it is desired to position is located within the inner gimbal 8. In practice, this coil may be adjusted in position that is, it may be rotated about its axis 12 relative to the inner gimbal 8, however, for purposes of the present discussion it may be assumed that the coil 10 is fixedin position to the inner gimbal 8. The coil 10 is located around the neck 13 of the cathode ray tube which, as indicated, is also in a fixed position relative to the chassis. The long axis of the cathode ray tube is indicated by the dot 12 (FIG. 1).

The supporting pin arrangements permit the inner and outer gimbals to rotate about their axis x and y, respectively. They also pennit the gimbals initially to be adjusted in the axial direction. For example, pins 14 and .16 may be secured at 18 and 20 respectively to the outer gimbal 6 and may be rotatably mounted at their opposite ends in the outer ring 2. A screw 50 which threads into an opening in the pin 14, when adjusted, causes the outer gimbal 6 and inner gimbal 8 to move in the direction of the y axis. The coil'spring 52 maintains the other pin 16 biased relative to the supporting ring 2 to take up any slack which results during the adjustment of the screw 50. A similar arrangement is provided for the pins 32 and 34 which support the inner gimbal 8 for movement about the x axis.

The gimbal 6 includes a first arm 26 and a second arm 28. These two arms are approximately at right angles to one another and, in the initial position of the inner gimbal, also at right angles to the long axis 12 of the tube. An adjustment screw 30 threaded into an opening at the end of arm 28 abuts, at its free end, the supporting ring 2. The shank of this screw extends in the general direction of the tube axis 12. The inner gimbal is formed with an arm 44 which extends at an angle of about 45 from the x and y axis and about 90 from the tube axis 12, in the initial position of the inner gimbal. This arm is formed with an extension 47 having a threaded opening therein which is directly above the arm 26 on the outer gimbal 6. An adjustment screw 46 located in this opening and extending in the general direction of axis 12 abuts this arm 26 at the free end of the screw 46.

A spring 48 which serves as a biasing means is connected from the end portion of the arm 44 to the chassis, as indicated by symbol 49. Alternatively, two arms may be used in place of the arm 44. One arm would extend from the gimbal 8 directly over the arm 26 and hold the screw 46 in contact with arm 26. The second arm would extend from the gimbal 8 at an angle of about 45 from the x and y axis and about 90 from the tube axis 12, and would have the spring 48 attached to it.

In the operation of the arrangement of the present invention, adjustment of the adjustment screw 30 rotates the outer gimbal 6 and inner gimbal 8 about the y axis. Note that the arm 28 and its adjustment screw 30 are located at a substantial angle (about 80 or so) from the y axis so that translation about the y axis is relatively easy. The optimum position for the adjustment screw would be at about 90, however, if it were placed there it would block access to the adjusting screw 54.

In similar fashion adjustment of the adjustment screw 46 rotates the inner gimbal 8 about its x axis and this rotation is relative to the outer gimbal 6. As already mentioned, the screw 46 is threaded into an opening of the extension 47 of the arm-44 on the inner gimbal and it bears against the arm 26 on the outer gimbal 6.

As should be clear from the discussion up'to this point the adjustment of the inner and outer gimbals changes the position of the coil 10 which is secured to the inner gimbal. The single coil spring 48 secured to the end of arm 44 holds the two gimbal rings in the positions to which they have been adjusted. Because the adjustment of the outer gimbal is relative to the outer supporting ring and the adjustment of the inner ring is relative to the outer gimbal, it is possible to bias the arrangement by only a single spring as should be clear from the figures.

Some important features of the present arrangement are that all adjustments are easy to make. The nurled knobs on the adjustment screws are easy to access and do not interfere with the adjustment of the gimbals in the direction of the x and y axis by the screws 50 and 54. In addition, the arrangement is such that a single spring 48 may be used to maintain the gimbals in the position to which it has been adjusted.

What is claimed is:

1. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axes, perpendicular to one another and to the long axis of the tube comprising, in combination:

an inner gimbal supporting said coil;

an outer gimbal supporting said inner gimbal for permitting tilting of the inner gimbal about the inner gimbal axis;

a gimbal supporting structure fixed to a chassis supporting said outer gimbal for permitting tilting of the outer gimbal about the outer gimbal axis;

adjusting means mounted between the inner and outer gimbals for tilting the inner gimbal about its axis;

adjusting means mounted between the outer gimbal and the gimbal supporting structure for tilting the outer gimbal about its axis;

and biasing means coupling the inner gimbal to said chassis for maintaining the inner and outer gimbals in the positions to which they have been adjusted. 2. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axes, perpendicular to one another and to the long axis of the tube comprising, in combination:

a gimbal supporting structure fixed to a chassis; an outer gimbal supported in said gimbal supporting structure for permitting said outer gimbal to tilt about the outer gimbal axis, said outer gimbal having first and second arms extending therefrom at an angle of substantially 90 from one another;

adjusting means mounted between said second arm and said gimbal supporting structure for tilting said outer gimbal about the outer gimbal axis; an inner gimbal supporting said coil, said inner gimbal being supported in said outer gimbal for permitting said inner gimbal to tilt about the inner gimbal axis, said inner gimbal having at least one arm extending therefrom at an acute angle from the inner and outer gimbals axes;

adjusting means mounted between said one arm of said inner gimbal and said first arm of said outer gimbal for tilting said inner gimbal about the inner gimbal axis; and

biasing means coupling said inner gimbal to said chassis for maintaining said inner and outer gimbals in the positions to which they have been tilted.

3. The combination claimed in claim 2 said acute angle being substantially 45.

4. The combination claimed in claim 2 said biasing means comprising a spring.

5. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axis, perpendicular to one another and to the long axis of the tube comprising, in combination:

a gimbal supporting structure fixed to a chassis;

means for supporting an outer gimbal in said gimbal supporting structure for permitting said outer gimbal to tilt about the outer gimbal axis, said outer gimbal having first and second arms extending therefrom at an angle of substantially 90 from one another;

adjustable screw means mounted between said second arm and said gimbal supporting structure for tilting said outer gimbal about the outer gimbal axis; means for supporting an inner gimbal in said outer gimbal for permitting said inner gimbal to tilt about the inner gimbal axis, said inner gimbal supporting said coil, and having an arm extending from said inner gimbal at an angle of about 45 from the inner and outer gimbal axes,

said arm including an extension which lies directly above 1 said first arm of said outer gimbal;

adjustable screw means mounted between said extension and said first arm of said outer gimbal for tilting said inner gimbal about the inner gimbal axis; and

biasing means coupling said arm of said inner gimbal to said chassis for maintaining said inner and outer gimbals in the positions to which they have been adjusted.

6. The combination claimed in claim 5 said means for supporting said outer gimbal in said gimbal supporting structure comprising a pair of pins each having one end secured to said outer gimbal and the other end rotatably mounted in said gimbal supporting structure.

7. The combination claimed in claim 5 said means for supporting said inner gimbal in said outer gimbal comprising a pair of pins each having one end secured in said inner gimbal and the other end rotatably mounted in said outer gimbal.

8. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axes substantially normal to one another and to the long axis of the two comprising, in combination:

first means pivotable about a first axis supporting said coilsecond means pivotable about a second axis substantially normal to said first axis supporting said first means about said first axis while permitting said first means to pivot about said first axis;

mechanical reference support means supporting said second means about said second axis while permitting said second means to pivot about said second axis;

first adjusting means coupling said first and second means for permitting the adjustment of said first means about its axis relative to said second means;

second adjusting means coupling said second means to said support means for adjusting said second means about its axis relative to said reference means; and

biasing means coupling the first means to said reference means for maintaining said first and second means in the positions to which they have been adjusted. 9. The combination as set forth in claim 8 wherein said first means further includes means adjusting said first means along said first axis.

10. The combination as set forth in claim 8 wherein said second means further includes means adjusting said second means along said second axis.

11. The combination as set forth in claim 8 wherein said first and second means each include additional means for adjusting each means along its respective axis to thereby cause the movement of said coil in a plane perpendicular to said long axis.

12. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axes, perpendicular to one another and to the long axis of the tube comprising, in combination:

a gimbal supporting structure fixed to a chassis; an outer gimbal supported in said gimbal supporting structure for permitting said outer gimbal to tilt about the outer gimbal axis, said outer gimbal having an arm extending therefrom at a substantial angle from said axis;

adjusting means mounted between said arm and said gimbal supporting structure for tilting said outer gimbal about the outer gimbal axis; an inner gimbal supporting said coil, said inner gimbal being supported in said outer gimbal for permitting said inner gimbal to tilt about the inner gimbal axis, said inner gimbal having at least one arm extending therefrom at an acute angle from the inner and outer gimbals axes;

adjusting means mounted between said one arm of said inner gimbal and said outer gimbal for tilting said inner gimbal about the inner gimbal axis; and

biasing means coupling said inner gimbal to said chassis for maintaining said inner and outer gimbals in the positions to which they have been tilted.

s: s s a 

1. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axes, perpendicular to one another and to the long axis of the tube comprising, in combination: an inner gimbal supporting said coil; an outer gimbal supporting said inner gimbal for permitting tilting of the inner gimbal about the inner gimbal axis; a gimbal supporting structure fixed to a chassis supporting said outer gimbal for permitting tilting of the outer gimbal about the outer gimbal axis; adjusting means mounted between the inner and outer gimbals for tilting the inner gimbal about its axis; adjusting means mounted between the outer gimbal and the gimbal supporting structure for tilting the outer gimbal about its axis; and biasing means coupling the inner gimbal to said chassis for maintaining the inner and outer gimbals in the positions to which they have been adjusted.
 2. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axes, perpendicular to one another and to the long axis of the tube comprising, in combination: a gimbal supporting structure fixed to a chassis; an outer gimbal supported in said gimbal supporting structure for permitting said outer gimbal to tilt about the outer gimbal axis, said outer gimbal having first and second arms extending therefrom at an angle of substantially 90* from one another; adjusting means mounted between said second arm and said gimbal supporting structure for tilting said outer gimbal about the outer gimbal axis; an inner gimbal supporting said coil, said inner gimbal being supported in said outer gimbal for permitting said inner gimbal to tilt about the inner gimbal axis, said inner gimbal having at least one arm extending therefrom at an acute angle from the inner and outer gimbals axes; adjusting means mounted between said one arm of said inner gimbal and said first arm of said outer gimbal for tilting said inner gimbal about the inner gimbal axis; and biasing means coupling said inner gimbal to said chassis for maintaining said inner and outer gimbals in the positions to which they have been tilted.
 3. The combination claimed in claim 2 said acute angle being substantially 45* .
 4. The combination claimed in claim 2 said biasing means comprising a spring.
 5. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axis, perpendicular to one another and to the long axis of the tube comprising, in combination: a gimbal supporting structure fixed to a chassis; means for supporting an outer gimbal in said gimbal supporting structure for permitting said outer gimbal to tilt about the outer gimbal axis, said outer gimbal having first and second arms extending therefrom at an angle of substantially 90* from one another; adjustable screw means mounted between said second arm and said gimbal supporting structure for tilting said outer gimbal about the outer gimbal axis; means for supporting an inner gimbal in said outer gimbal for permitting said inner gimbal to tilt about the inner gimbal axis, said inner gimbal supporting said coil, and having an arm extending from said inner gimbal at an angle of about 45* from the inner and outer gimbal axes, said arm includiNg an extension which lies directly above said first arm of said outer gimbal; adjustable screw means mounted between said extension and said first arm of said outer gimbal for tilting said inner gimbal about the inner gimbal axis; and biasing means coupling said arm of said inner gimbal to said chassis for maintaining said inner and outer gimbals in the positions to which they have been adjusted.
 6. The combination claimed in claim 5 said means for supporting said outer gimbal in said gimbal supporting structure comprising a pair of pins each having one end secured to said outer gimbal and the other end rotatably mounted in said gimbal supporting structure.
 7. The combination claimed in claim 5 said means for supporting said inner gimbal in said outer gimbal comprising a pair of pins each having one end secured in said inner gimbal and the other end rotatably mounted in said outer gimbal.
 8. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axes substantially normal to one another and to the long axis of the two comprising, in combination: first means pivotable about a first axis supporting said coil; second means pivotable about a second axis substantially normal to said first axis supporting said first means about said first axis while permitting said first means to pivot about said first axis; mechanical reference support means supporting said second means about said second axis while permitting said second means to pivot about said second axis; first adjusting means coupling said first and second means for permitting the adjustment of said first means about its axis relative to said second means; second adjusting means coupling said second means to said support means for adjusting said second means about its axis relative to said reference means; and biasing means coupling the first means to said reference means for maintaining said first and second means in the positions to which they have been adjusted.
 9. The combination as set forth in claim 8 wherein said first means further includes means adjusting said first means along said first axis.
 10. The combination as set forth in claim 8 wherein said second means further includes means adjusting said second means along said second axis.
 11. The combination as set forth in claim 8 wherein said first and second means each include additional means for adjusting each means along its respective axis to thereby cause the movement of said coil in a plane perpendicular to said long axis.
 12. An arrangement for suspending a coil of a cathode ray tube about the neck of the tube and for tilting the coil about two axes, perpendicular to one another and to the long axis of the tube comprising, in combination: a gimbal supporting structure fixed to a chassis; an outer gimbal supported in said gimbal supporting structure for permitting said outer gimbal to tilt about the outer gimbal axis, said outer gimbal having an arm extending therefrom at a substantial angle from said axis; adjusting means mounted between said arm and said gimbal supporting structure for tilting said outer gimbal about the outer gimbal axis; an inner gimbal supporting said coil, said inner gimbal being supported in said outer gimbal for permitting said inner gimbal to tilt about the inner gimbal axis, said inner gimbal having at least one arm extending therefrom at an acute angle from the inner and outer gimbals'' axes; adjusting means mounted between said one arm of said inner gimbal and said outer gimbal for tilting said inner gimbal about the inner gimbal axis; and biasing means coupling said inner gimbal to said chassis for maintaining said inner and outer gimbals in the positions to which they have been tilted. 